From e1b91eb195734e3eeffdba39bccd6647e34f70f3 Mon Sep 17 00:00:00 2001 From: Niklas Haas Date: Sun, 9 Jun 2024 14:43:11 +0200 Subject: [PATCH] avdovi/dovi_rpudec: handle prev_vdr_rpu_id failures According to the spec, missing previous VDR RPU IDs do not constitute an error, but we should instead fallback first to VDR RPU with ID 0, and failing that, synthesize "neutral" metadata. That's nontrivial though as the resulting metadata will be dependent on other properties of the RPU, and this case is not hit in practice so I'll defer it to a rainy day. --- libavcodec/dovi_rpudec.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/libavcodec/dovi_rpudec.c b/libavcodec/dovi_rpudec.c index 306efbb31f..109cef5742 100644 --- a/libavcodec/dovi_rpudec.c +++ b/libavcodec/dovi_rpudec.c @@ -456,7 +456,12 @@ int ff_dovi_rpu_parse(DOVIContext *s, const uint8_t *rpu, size_t rpu_size, if (use_prev_vdr_rpu) { int prev_vdr_rpu_id = get_ue_golomb_31(gb); VALIDATE(prev_vdr_rpu_id, 0, DOVI_MAX_DM_ID); + if (!s->vdr[prev_vdr_rpu_id]) + prev_vdr_rpu_id = 0; if (!s->vdr[prev_vdr_rpu_id]) { + /* FIXME: Technically, the spec says that in this case we should + * synthesize "neutral" vdr metadata, but easier to just error + * out as this corner case is not hit in practice */ av_log(s->logctx, AV_LOG_ERROR, "Unknown previous RPU ID: %u\n", prev_vdr_rpu_id); goto fail;